1. Field of the Invention
The invention relates to a device for retaining a foot or a boot on a sports apparatus, in which the retention of the foot or boot is accomplished by means of at least one strap or linkage. The invention also relates to a strap or linkage adapted to be integral with the device.
2. Description of Background and Relevant Information
Devices of the aforementioned type are used for snowboarding, snow skiing, water skiing, snowshoeing, roller skating, surfing, and other activities.
A device using straps/linkages according to the prior art generally has a lateral portion and a medial portion which demarcate therebetween a zone for receiving the foot or the boot, as well as a rear support element, or highback, associated with at least one of the lateral and medial portions. The rear support element has a support surface facing the receiving zone and adapted to receive the rear of a lower leg of the user. The rear support element also has a free surface opposite the support surface. The device also has at least one linkage that extends between the lateral and medial portions, each linkage being used to retain the foot or the boot in the receiving zone.
The linkage is generally an elongated piece that is relatively flexible and substantially inextensible. Its flexibility enables it to adapt to the foot or to the boot. Its relative inextensibility promotes the retention of the foot or of the boot in the receiving zone.
Two linkages are frequently used on a device, one in the area of the metatarsophalangeal joint of the foot, the other in the area of the instep. The one which acts toward the instep is generally oriented so as to bias the foot or the boot toward both the receiving zone and the rear support element.
That is the case, for example, in snowboarding where a user must be supported at the rear. By having the lower leg in constant contact with the rear support element, steering precision can be assured.
However, it has been recognized that the retention of the heel in known devices is not always adequate, and that play can be created beneath the heel of the foot or boot. The application of forces in steering the apparatus, such as a snowboard, can induce heel movement.
For example, in snowboarding, a setting of the front running edge can cause the heel to be raised, which hinders steering precision.
In order to improve the retention of the heel, the prior art has proposed solutions.
One of these solutions, according to U.S. Pat. No. 6,206,403, involves using a linkage device, in the area of the heel, which has a front strap part and a rear strap part. The front strap is at the front of the lower leg and substantially above the instep, whereas the rear strap is at the rear of the lower leg and above the heel. The front and rear parts are joined to encircle the lower leg just above the heel. When the belt formed by the parts of the linkage device is properly tightened, the heel is retained with precision in the receiving zone. Thus, the amount of play created beneath the heel of the foot or the boot is reduced. However, it has been noted that a substantial amount of movement is formed between the rear of the lower leg and the rear support element. The movement hinders the support provided at the rear.
This is particularly the case in snowboarding when the user exerts supporting forces on the rear running edge. The leg extension movement is disturbed by the elimination of the aforementioned play. This hinders steering precision.
Thus, the device according to the document U.S. Pat. No. 6,206,403 improves the holding of the foot or boot beneath the heel, but it worsens it between the rear of the lower leg and the rear support element, which is an advantage, on the one hand, and a drawback, on the other hand.